Neural Response Suppression Predicts Repetition Priming of Spoken Words and Pseudowords

Abstract

Abstract& An important method for studying how the brain processes familiar stimuli is to present the same item on more than one occasion and measure how responses change with repetition. Here we use repetition priming in a sparse functional magnetic resonance imaging (fMRI) study to probe the neuroanatomical basis of spoken word recognition and the representations of spoken words that mediate repetition priming effects. Participants made lexical decisions to words and pseudowords spoken by a male or female voice that were presented twice, with half of the repetitions in a different voice. Behavioral and neural priming was observed for both words and pseudowords and was not affected by voice changes. The fMRI data revealed an elevated response to words compared to pseudowords in both posterior and anterior temporal regions, suggesting that both contribute to word recognition. Both reduced and elevated activation for second presentations (repetition suppression and enhancement) were observed in frontal and posterior regions. Correlations between behavioral priming and neural repetition suppression were observed in frontal regions, suggesting that repetition priming effects for spoken words reflect changes within systems involved in generating behavioral responses. Based on the current results, these processes are sufficiently abstract to display priming despite changes in the physical form of the stimulus and operate equivalently for words and pseudowords. &

Where sound position influences sound object representations: A 7-T fMRI study

“…Multiple levels of representation are likely to exist also for other auditory features, such as the physical properties of the sound track or stimulus familiarity, as recently indicated by fMRI priming studies (De Lucia et al, 2009). The behavioural priming effect, i.e., shorter reaction times, has been reported for words, independently of whether they were repeated by the same or a different speaker (Gagnepain et al, 2008;Orfanidou et al, 2006). The priming suppression of the BOLD response and shorter response latency occurred, however, differentially in different parts of the temporal regions, suggesting the coexistence of speaker-dependent and speaker-invariant auditory word representations.…”

Perceptual learning of noise vocoded words: Effects of feedback and lexicality.

“…There were no significant differences in any of these properties across the two groups. The words were originally recorded by a 20-year-old female speaker of southern British English for a previous study (Orfanidou, Marslen-Wilson, & Davis, 2006). For the full list of words, see Appendix A.…”

“…The nonwords were matched to the 120 word stimuli on the basis of overall phonemic composition of the two groups, such that each of the 120-item word and nonword groups contained the same overall distribution of phonemes. These words and nonwords were recorded by the same female speaker of southern British English in the same session as the stimuli used for Experiment 1 (see Orfanidou et al, 2006) and were noise vocoded in the same way as Groups A, B, and C. The stimuli in these two training groups were then assembled to make triplets providing feedback for the listeners, as in the DCD condition of Experiment 1. Each NV stimulus (D) was followed by a clear version (C) followed by the distorted version again (D), with a 1-s gap between the repetitions of the stimuli, to make sets of 120 word (W) and nonword (N) DCD triplets.…”

Spoken Word Memory Traces within the Human Auditory Cortex Revealed by Repetition Priming and Functional Magnetic Resonance Imaging

“…Concerning auditory repetition priming, neuroimaging studies have previously failed to confirm the involvement of the auditory cortex (Badgaiyan et al, 1999(Badgaiyan et al, , 2001Carlesimo et al, 2004;Orfanidou et al, 2006) (for neuropsychological evidence, see also Swick et al, 2004). However, a large body of behavioral evidence suggests that this phenomenon is indeed mediated by perceptual representations (Schacter and Church, 1992;Church and Schacter, 1994), i.e., by the auditory cortex.…”